The whole body retention at any time t-t of the fraction of initial radioe-tivity
inputed at time rt is
Ex ,e (AK;i )(t-T) .
Thus, the instantaneous activity at time t-T that remains following input during
dt is
AEPo e
~(Kgta )t r x e ~(A+K; ) (t=) dt
It follows that the instantaneous activity at time t-t that remains following
input during T is
e
T
~(Kgti)t
AA tK Cet)
J ° A£,P%e
r.X.e
dt.
i*i
The solution of the integral yields a general expression that depends on
the user defining t.
For example, if t is the fixed uptake interval, T, plus an
additional fixed post uptake interval, 9, then the body burden at T+ @ is
given by
“(A
+Ke)T
APP fF, Lixzg Ce (A*Kg)
“CA+K,)T
-e (A+R) de
CA 4K;
*ki) 0
K. - K,
As previously stated, Eq. (2) applied at Rongelap and Utirik, it was
for the situation that variable time ¢ was the uptake interval.
Additionally,
persons who returned to the atolls in June 1954 and June 1957 did so with an ini-~
tial body burden, q®.
The behavior of this contribution to body burden,
q, was embodied in the q° term of Eq. (2).
A similar model was used to relate